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From Eranda Sooriyabandara <erandaj...@gmail.com>
Subject Re: JIRA Issues that would nice to have a Graphical Query Plan Attached
Date Wed, 14 Jul 2010 04:02:17 GMT
Hi Nirmal,
Thanks for the details and I will go through it.

>>SELECT a.USER_ID, a.USER_NAME, b.account_id FROM Users a JOIN
Messaged_Users b ON a.USER_ID=b.USER_ID AND b.account_id=(?)
It is not a sql query. It's a prepared statement.

if you are using ij you can do it as follows
ij> prepare s1 as 'SELECT a.USER_ID, a.USER_NAME, b.account_id FROM Users a
JOIN
Messaged_Users b ON a.USER_ID=b.USER_ID AND b.account_id=(?)'
and then the execution
ij> execute s1 using 'values(1)';    <===== This should be tracked

Thanks
Eranda

On Tue, Jul 13, 2010 at 10:29 PM, Nirmal Fernando <nirmal070125@gmail.com>wrote:

> Hi Eranda,
>
> Please see my comments inline.
>
> > Did you do it to prepared statement?
>
> I did it for this query:
> SELECT a.USER_ID, a.USER_NAME, b.account_id FROM Users a JOIN
> Messaged_Users b ON a.USER_ID=b.USER_ID AND b.account_id=(?)
>
> I suppose you need to know the query plan followed by the optimizer,
> for that query.
>
> > Also need a little explanation to understand the doc.
>
> It's still in very basic HTML stage, sorry if it's not that clear.
> It displays the plan followed by the optimizer as a tree.
> In this case query has executed like:
>
> PROJECTION
>     |
>     |
> HASHJOIN
>     |
>  _  |_____________
> |                           |
> TABLESCAN         HASHSCAN
>
> Under each node selected portion of details are shown
> if they're not null.
>
> If you want to know the meanings of entries in tables
> you can refer to sysxplain tables
> (http://db.apache.org/derby/docs/dev/ref/rref_xplain_tables.html).
>
> Thanks.
>
> > Thanks
> > Eranda
> >
> > On Tue, Jul 13, 2010 at 9:39 PM, Nirmal Fernando <nirmal070125@gmail.com
> >
> > wrote:
> >>
> >> Hi Eranda,
> >>
> >> I've attached a PDF to the JIRA issue.
> >>
> >> Thanks for the request!
> >>
> >> On Tue, Jul 13, 2010 at 2:09 PM, Eranda Sooriyabandara
> >> <erandajira@gmail.com> wrote:
> >> >
> >> > Hi Nirmal,
> >> > Can you do it for the following issue
> >> > https://issues.apache.org/jira/browse/DERBY-3892
> >> > Thanks
> >> > Eranda
> >> > On Tue, Jul 13, 2010 at 12:47 PM, Nirmal Fernando
> >> > <nirmal070125@gmail.com> wrote:
> >> >>
> >> >> Hi All,
> >> >>
> >> >> These days we're testing the basic HTMLs generated using
> >> >> PlanExporter tool. So, I would really happy to attach Graphical Query
> >> >> Plans
> >> >> for JIRA issues which may possibly helpful to understand where's
> >> >> the problem.
> >> >>
> >> >> If you know any issues that generates wrong results please reply to
> >> >> this thread,
> >> >> with the link to the JIRA. It would be nice if you have sql commands
> to
> >> >> setup
> >> >> the environment needed to that issue.
> >> >>
> >> >> Please note that issues with exceptions/assert failure can't import
> to
> >> >> a Graphical Query Plan,
> >> >> since as for those queries, there's no statistics captured by Xplain
> >> >> tables.
> >> >>
> >> >> Thanks.
> >> >>
> >> >> --
> >> >> Best Regards,
> >> >> Nirmal
> >> >>
> >> >> C.S.Nirmal J. Fernando
> >> >> Department of Computer Science & Engineering,
> >> >> Faculty of Engineering,
> >> >> University of Moratuwa,
> >> >> Sri Lanka.
> >> >>
> >> >
> >>
> >>
> >>
> >> --
> >> Best Regards,
> >> Nirmal
> >>
> >> C.S.Nirmal J. Fernando
> >> Department of Computer Science & Engineering,
> >> Faculty of Engineering,
> >> University of Moratuwa,
> >> Sri Lanka.
> >
> >
>
>
>
> --
> Best Regards,
> Nirmal
>
> C.S.Nirmal J. Fernando
> Department of Computer Science & Engineering,
> Faculty of Engineering,
> University of Moratuwa,
> Sri Lanka.
>

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